Whether you are explaining WordPress, or just sharing your gaming highlights, screen-grabbing is the way to go. Snagit makes it easy to share images and video, and 9to5Toys Specials has it for $25.
This app for Mac and PC is designed to provide an all-in-one workflow for sharing the content on your screen. Once you set up a custom hotkey, you can make an instant grab at any time. This includes capturing whole web pages, when you would otherwise need to scroll. Once you have captured what you want to share, you can crop and annotate your screenshots, and trim away unnecessary parts of video grabs. The Steps feature is particularly neat: it allows you to create step-by-step instructions for the recipient to follow. Once you are done editing, your image or video can be easily exported.
The license lets you install the app on two devices, and the current deal is half price off the MSRP.